{"id":87,"date":"2009-04-14T13:21:21","date_gmt":"2009-04-14T20:21:21","guid":{"rendered":"https:\/\/davidstipes.net\/?p=87"},"modified":"2010-01-16T00:20:43","modified_gmt":"2010-01-16T07:20:43","slug":"how-to-use-a-perspective-cube","status":"publish","type":"post","link":"https:\/\/davidstipes.net\/?p=87","title":{"rendered":"How to use a Perspective Cube"},"content":{"rendered":"

New visual effects students often have difficulty with the concept and application of the “perspective cube.”\u00a0 A perspective cube is a well constructed\u00a0box with accurate parallel edges and right angles.\u00a0 Usually it is white with black lines along the edges. Typical construction materials would be white foam core and\u00a0one inch black paper tape along the\u00a0edges.\u00a0<\/p>\n

The cube size is somewhat to taste and per your transportation restrictions but it should not be too small. Most appear to be 12″ x 12″ x 12″\u00a0\u00a0 or 18″ x 18″ x 18″.\u00a0\u00a0 I suggest using whole inch measurements and make all side equal as that facilitates quicker set up and ease of reproduction in a Computer Generated Imagery (CGI) environment if needed.\u00a0<\/p>\n

\"picture1\"The perspective cube can be used for multiple reasons. Today we will use the perspective cube to find a horizon line that can’t be seen.\u00a0\u00a0<\/p>\n

Suppose you are on location where mountains or vegetation blocks your view of a horizon line and you have no other man-made structures to run perspective lines from to find a vanishing point and horizon line.\u00a0<\/p>\n

\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Set your camera for the shot you want, then place the perspective cube in the scene.\u00a0 It is imperative that the perspective cube NOT be hand held as accuracy depends upon the cube being level side to side and front to back. So, place your cube on a tripod or “C” stand (grip-stand).\u00a0<\/p>\n

\u00a0\u00a0\"picture2\"\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Rotate the cube so the camera sees two of the sides or the sides and top. Use a level tool on the top of the cube to insure accuracy.\u00a0<\/p>\n

Take your exposures of the cube for later reference, remove the cube and shoot your scene as normal.\u00a0\u00a0<\/p>\n

In Photoshop or similar program, you can run lines out from the parallel cube edges to vanishing points. Since you will see at least two sides, you will have two vanishing points.<\/p>\n

\"picture32\"<\/p>\n

Run a line between\u00a0the vanishing points\u00a0and you will have a horizon line to base your matte painting or effects upon.<\/p>\n

\"picture4\"<\/p>\n

(Horizon line information is needed to accurately place objects in the scene so they will not appear pitched over or tilted.\u00a0 If a building’s vanishing point is not on the horizon line it will appear to be\u00a0 pitching down into the ground or aiming up out of the ground. It is also used to do accurate sky & cloud replacement. Yep, clouds have perspective, too!)\u00a0\u00a0<\/p>\n

Photo courtesy of Jeff Burgess at www.jdburgessonline.com<\/a><\/h6>\n

\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"

New visual effects students often have difficulty with the concept and application of the “perspective cube.”\u00a0 A perspective cube is a well constructed\u00a0box with accurate parallel edges and right angles.\u00a0 Usually it is white with black lines along the edges. Typical construction materials would be white foam core and\u00a0one inch black paper tape along the\u00a0edges.\u00a0 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12,19,34],"tags":[43,80,81,56,30,15,17,82,78],"class_list":["post-87","post","type-post","status-publish","format-standard","hentry","category-education","category-film-vfx-history","category-visual-effects-techniques","tag-cgi","tag-education","tag-matte-painting","tag-perspective-cube","tag-stipes-universe","tag-students","tag-the-art-institute-of-phoenix","tag-tutorials","tag-visual-effects"],"_links":{"self":[{"href":"https:\/\/davidstipes.net\/index.php?rest_route=\/wp\/v2\/posts\/87","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/davidstipes.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/davidstipes.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/davidstipes.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/davidstipes.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=87"}],"version-history":[{"count":15,"href":"https:\/\/davidstipes.net\/index.php?rest_route=\/wp\/v2\/posts\/87\/revisions"}],"predecessor-version":[{"id":96,"href":"https:\/\/davidstipes.net\/index.php?rest_route=\/wp\/v2\/posts\/87\/revisions\/96"}],"wp:attachment":[{"href":"https:\/\/davidstipes.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=87"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/davidstipes.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=87"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/davidstipes.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=87"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}